package suanfa;

import java.util.Stack;

public class test9 {
    Stack<Integer> s1 = new Stack<>();
    Stack<Integer> s2 = new Stack<>();
    private int front;

    public void MyQueue() {

    }

    /**
     * Push element x to the back of queue.
     */


    public void push(int x) {
        if (s1.empty())
            front = x;
        while (!s1.isEmpty())
            s2.push(s1.pop());
        s2.push(x);
        while (!s2.isEmpty())
            s1.push(s2.pop());
    }


    /**
     * Removes the element from in front of queue and returns that element.
     */
    public void pop() {
        s1.pop();
        if (!s1.empty())
            front = s1.peek();
    }


    /**
     * Get the front element.
     */
    public int peek() {
        return front;
    }

    /**
     * Returns whether the queue is empty.
     */
    public boolean empty() {
        return s1.isEmpty();

    }
}
